you want to put something on top of that white piece? Does the hutch part lift off? if not, the fabricator will need to cut it to fit an also fabricate and edge that will cover the top that's already there. (unless you plan on removing it)

Instead of doing all of that, why don't you find some wall paper, or paint/stencil, and do the back of that piece, including the back on the inside of the hutch.

basically something like this, but you would do the back part behind the top.

pick a fabric, wallpaper, or paint and a stencil that match your kitchen.

We did a wood top on this built in so that it matched the flooring in the dining room.